Establishes standards in regards to the tracking of gun purchases by financial institutions

HB 2778 prohibits financial institutions in Missouri from discriminating against firearms retailers by refusing payment card transactions, charging higher fees, or limiting business based on whether a merchant uses the specific "firearms code" merchant category. The bill also bans these institutions from creating or maintaining lists of privately owned firearms or their owners, with exceptions for criminal investigations and legal requirements. To enforce these rules, the Attorney General can investigate violations and issue notices requiring immediate cessation of discriminatory practices, while affected merchants or customers can petition for an investigation or seek court injunctions if the agency does not act. Additionally, the law prevents financial institutions from disclosing financial records containing the firearms code if it was collected in violation of the bill, and it allows for civil penalties and the recovery of legal fees for those who successfully enforce the statute.